Sudden Cardiac Arrest in Pediatrics

CME REVIEW ARTICLE

RoseAnn L. Scheller, MD,* Laurie Johnson, MD, MS,† Angela Lorts, MD, MS,‡ and Thomas D. Ryan, MD, PhD‡

with fluid boluses, performance of diagnostic studies, and initiation Abstract: Sudden cardiac arrest (SCA) in the pediatric population is a of inotropes. Chest radiograph and electrocardiogram (ECG) ob- rare and potentially devastating occurrence. An understanding of the differ- tained in the ED were suspicious for underlying cardiac etiology ential diagnosis for the etiology of the cardiac arrest allows for the most ef- of his arrest. Echocardiography performed in the pediatric in- fective emergency care and provides the patient with the best possible tensive care unit (ICU) led to a diagnosis of hypertrophic outcome. Pediatric SCA can occur with or without prodromal symptoms cardiomyopathy (HCM).1 and may occur during exercise or rest. The most common cause is arrhyth- Sudden cardiac arrest (SCA) occurs when cardiac output rap- mia secondary to an underlying channelopathy, cardiomyopathy, or myocar- idly declines and will result in sudden cardiac death (SCD) if car- ditis. After stabilization, evaluation should include electrocardiogram, chest diac function is not restored quickly. Sudden cardiac death is radiograph, and echocardiogram. Management should focus on decreasing further defined as a rapid and unsuspected death due to a cardio- the potential for recurring arrhythmia, maintaining cardiac preload, and vascular cause, typically within 1 hour from the onset of symp- thoughtful medication use to prevent exacerbation of the underlying condi- toms and usually occurring in a patient previously considered tion. The purpose of this review was to provide the emergency physician healthy.2 When resuscitation is successful, the term “aborted car- with a concise and current review of the incidence, differential diagnosis, diac death” is sometimes used, although SCA alone may suffice. and management of pediatric patients presenting with SCA. In discussion of SCA in pediatrics, children aged 12 months are Key Words: cardiac arrest, cardiovascular disease, excluded from most definitions because of more variable etiolo- hypertrophic cardiomyopathy, channelopathy, arrhythmia gies involved.3 Sudden cardiac arrest in children is relatively un- 4 – common compared with adult cases of cardiac arrest. Due to (Pediatr Emer Care 2016;32: 630 638) the uncommon occurrence of pediatric SCA and SCD, these cases are particularly devastating for families, schools, and entire com- TARGET AUDIENCE munities.5 This review focuses on the cardiac etiologies of pediat- This CME activity is intended for emergency physicians, ric SCA, with the goal of maximizing resuscitative efforts to nurses, hospitalists, and general pediatricians. prevent progression to SCD and result in favorable outcomes in patients who experience SCA. Specific treatment of cardiac con- LEARNING OBJECTIVES ditions is not discussed, but rather emergency evaluation of After completion of this article, the reader should be able to: suspected SCA. 1. Outline the possible cardiac causes of sudden arrest in children and adolescents. INCIDENCE 2. Describe emergency care of a pediatric sudden cardiac The true incidence for SCA and SCD is difficult to discern. arrest patient. This is due, in part, to the occasional unclear distinctions between 3. Identify disease-specific presentation of cardiac causes of arrest alone and arrest with death. In the current report, the terms sudden arrest in children and adolescents. will be used specifically to the reference cited, with joint use of the terms (SCA and SCD) if the exact meaning is unclear or not de- CASE scribed. Furthermore, most data for pediatric SCD are collected A previously healthy 5-year-old child experienced a sudden, post mortem, such that many cases of SCA or aborted SCD are of- unwitnessed collapse after sitting on a bench during recess. A ten not reported. Sudden unexpected death in childhood, which teacher discovered him pulseless and began bystander cardiopul- excludes patients younger than 12 months, is estimated at 1.3 monary resuscitation. After intubation by emergency medical re- per 100,000 patient years in the United States, of which cardiac sponders on the scene, he had spontaneous return of circulation. causes are estimated to be present in 30% of these cases.6 In addi- Upon arrival to the emergency department (ED), he was noted to tion, it is estimated that approximately 2000 patients younger than be persistently bradycardic and hypotensive. He received 2 doses 25 years will die from a sudden cardiac event each year in the of benzodiazepine for clinical findings concerning for seizure. Fur- United States,7 with an incidence estimated from 0.6 to 6.2 per ther evaluation included obtaining a focused history, resuscitation 100,000 persons.5 The incidence may be higher in athletes, with a relative risk of sudden death of 2.1 compared with nonathletes.8 These numbers have also evolved over the years and seem to *Pediatric Emergency Medicine Physician (Scheller), Division of Emergency 9–21 Medicine, Children's Mercy Hospitals & Clinics, Kansas City, MO; †Pediatric be increasing over time. Estimates differ because of unclear Emergency Medicine Physician (Johnson), Division of Emergency Medicine, definitions of terms, varied methods of reporting and collecting Cincinnati Children’s Hospital Medical Center; and ‡Pediatric Cardiologist data, and lack of mandatory reporting. Many of these reporting is- (Lorts, Ryan), Heart Institute, Cincinnati Children’s Hospital Medical Center, sues would be minimized with a standard reporting schema or a Cincinnati, OH. 22 The authors and staff in a position to control the content of this CME activity national registry. To further accurately define the incidence of and their spouses/life partners (if any) have disclosed that they have no SCD, the Centers for Disease Control and the National Institutes financial relationships with or financial interest in any commercial of Healthcare currently are enrolling patients into the “Sudden organizations pertaining to this educational activity. DeathintheYoungRegistry.” This registry began in September Reprints: RoseAnn L. Scheller, MD, Children's Mercy Hospitals & Clinics, 2401 Gillham Rd, Kansas City, MO 64108 (e‐mail: [email protected]). 2014 and includes all patients in 15 states who had sudden unex- Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. pected death due to an underlying medical cause, excluding ISSN: 0749-5161 trauma. The goal for this study is to further define the relative risk

630 www.pec-online.com Pediatric Emergency Care • Volume 32, Number 9, September 2016

Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Pediatric Emergency Care • Volume 32, Number 9, September 2016 Sudden Cardiac Arrest in Pediatrics by reviewing cases across several institutions to determine the right ventricular cardiomyopathy), and complete heart block.7 Ar- cause of death.23 rhythmias are demonstrated secondary to ion channelopathies in 4% of cases26 and may be the etiology of SCA even if no struc- UNDERLYING DIFFERENTIAL DIAGNOSES tural heart disease is found.28 Ventricular fibrillation (VF) is a The current review will summarize the literature pertaining much less commonly reported as a cause of SCA in children to SCA, which for the purposes of this discussion will also encom- (4%–10%) than in adults (50%).29,30 However, the lower reported pass aborted SCD. Cardiac conditions that can result in pediatric incidence in pediatric patients is likely an underestimate because SCA can be grouped into the following 3 general categories: struc- of lack of a documented initial rhythm at the time of collapse or tural cardiac defects, primary cardiac electrical abnormalities, and ac- because of the documentation of the rhythm, which occurred after quired conditions (due to certain drugs or chemical exposures, resuscitative efforts were initiated.9 secondary pulmonary artery hypertension or Eisenmenger syndrome, Electrophysiologic abnormalities can also be the result of and Commotio cordis). A list of etiologies is found in Table 1. specific exposures or ingestions. Therapeutic drugs that can result Structural etiologies include cardiomyopathies as well as in SCA by an arrhythmogenic mechanism include prescription congenital and postoperative cardiac lesions. The etiologies for medications such as erythromycin, carbamazepine, and ketocona- SCA are more likely to be congenital heart disease in the young zole, as well as overdoses of stimulant or psychotropic drugs. Il- child and related to arrhythmia in the adolescent.25 Congenital licit drug use, such as cocaine, or inhalation abuse of substances cardiac lesions are beyond the scope of this article and are not such as gasoline, glue, hair or cooking sprays, cigarette lighters discussed in detail. The most common structural defect discovered (also known as “huffing”) can also result in SCA.9 at the time of a SCA is HCM (36%). Other cardiac defects include coronary artery anomalies (17%), myocarditis (6%), and arrhyth- OVERALL PRESENTATION 26 mogenic ventricular dysplasia (4%). Sudden cardiac arrest can be the first presentation of an un- The most common mechanism leading to SCA is arrhyth- derlying cardiac disease, but occasionally, previous signs and mia, which can be secondary to an underlying channelopathy, 27 symptoms may help aid in the diagnosis. In cases of SCA cardiomyopathy, or myocarditis. Electrophysiological abnor- resulting in death in children, 61% had no known cardiac disease, malities include long QT syndrome (LQTS), Wolff-Parkinson-White 45% had previous symptoms remote to the event, and 26% had syndrome, Brugada syndrome, catecholaminergic polymorphic symptoms immediately preceding the event.31 Prodromal symp- ventricular tachycardia (CPVT), short QT syndrome (SQTS), ar- toms may be nonspecific, especially in children younger than rhythmogenic ventricular dysplasia (previously arrhythmogenic 10 years.32 When present, the most common antecedent symptoms were seizure, dyspnea, and syncope.31 Other preceding symptoms included chest pain, dizziness, and palpitations.7 Six- TABLE 1. Predisposing Cardiac Disorders for Pediatric SCA* teen percent of children experienced an event during moderate to vigorous activity, and exercise-associated SCD was more com- Structural/functional HCM mon in children aged 10 to 19 years.32 Coronary artery anomalies (AOCA, ALCAPA, Risk factors for SCA and SCD have been identified in adults, Kawasaki disease, etc) but few data exist regarding the pediatric population. It has been DCM reported that 4.5% of children with SCD had a positive family his- RCM tory of SCD in a first-degree relative.28 Hypertrophic cardiomyop- Myocarditis athy and many channelopathies are known to be genetic.24 In Congenital heart disease (tetralogy of Fallot, these familial cases, VF or ischemia-related arrhythmias are most transposition of the great arteries, hypoplastic likely the common final pathway in adults.33,34 left heart, etc) Other less-common causes: DISEASE-SPECIFIC PRESENTATION Aortic rupture Aortic valve stenosis Hypertrophic Cardiomyopathy Left ventricular outflow obstruction Hypertrophic cardiomyopathy is the most frequently identi- Mitral valve prolapse fied cause of SCD in young patients.26 It is the most common Coronary arteriosclerotic disease form of cardiomyopathy in the general population with a preva- Arrhythrogenic right ventricular dysplasia lence of 0.2% (1 in 500)35 and the second most common in pedi- Postoperative congenital heart disease atric and adolescent patients with an annual incidence of 0.47 in (after Fontan, Norwood angioplasty, 100,000.36 Potential causes of HCM are varied and more diverse transplantation surgeries, etc) in pediatric than adult populations. Inheritance in the familial form Electrophysiologic LQTS is generally autosomal dominant but often with variable pene- SQTS trance of the phenotype. Left ventricular hypertrophy, which CPVT may or may not encompass HCM, can also be acquired such as Wolf-Parkinson-White syndrome that seen in longstanding hypertension. Further investigation is necessary to better understand whether an increased risk for Brugada syndrome SCA or SCD exists in this form of hypertrophy. Two recent studies Complete heart block have reported long-term risk for SCD in pediatric and young adult Other Drugs/stimulants patients with HCM as 35 to 6%; however, the populations in- Commotiocordis cluded some patients with implantable cardioverter defibrillators Pulmonary hypertension (primary, secondary) and are not representative of undiagnosed patients.37,38 The presentation of HCM in children can range dramatically. *Adapted from Section on Cardiology and Cardiac Surgery,7 Berger and Campbell,9 and Campbell et al.24 Patients may be asymptomatic, may experience exertional symptoms such as fatigue, dyspnea, or chest pain, or may present in

Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Scheller et al Pediatric Emergency Care • Volume 32, Number 9, September 2016 cardiac arrest.39 The most common age of presentation is older usually have corrected QT intervals that are significantly prolonged than 10 years, but it may be diagnosed at any age. Presentation (>500 milliseconds), but 10% to 15% of patients with LQTS may at an earlier age is usually associated with a less favorable out- have a corrected QT that is normal.49 For CPVT, findings of base- come because of more rapid progression.40 line ECGs may be normal; however, during exercise stress testing, Physical examination may include a systolic ejection mur- ventricular ectopy is enhanced.50 mur most prominent at the right upper sternal border that im- Less common causes of arrhythmic channelopathies include proves with increased preload (such as with the patient gripping SQTS and Brugada syndrome, both of which are associated with the examiner's hand) as well as S3 and S4 sounds. Findings of SCD as the presenting sign. Presentation of SQTS can be at a very electrocardiograms are abnormal in 75% to 90% of patients with early age, whereas Brugada usually presents in adulthood, with the HCM, frequently with ST changes, T-wave inversions, and prom- more severe cases becoming apparent earlier.24 Rare causes of ar- inent Q waves, especially in the inferior and midprecordial leads rhythmia unrelated to channopathies include Wolff-Parkinson- (II, III, aVF,V1-V3).41,42 Noninvasive imaging is critical for diag- White syndrome, arrhythmogenic ventricular dysplasia, and com- nosis, including echocardiogram or cardiac magnetic resonance plete heart block. Wolff-Parkinson-White is caused by an anatomic imaging (MRI).39 anterograde accessory pathway and presents as tachyarrhythmia. Arrhythmogenic ventricular dysplasia, which most frequently pre- Coronary Artery Anomalies sents during adulthood, is a genetically determined cardiomyopathy The second most common cause of SCD in pediatric and ad- in which normal ventricular myocardium is replaced by fibrofatty olescent patients is coronary artery anomalies, with anomalous or- tissue that is ultimately arrhythmogenic.48 Complete heart block igin of a coronary artery (AOCA) from the opposite sinus of has a wide variety of causes and usually presents clinically as Valsalva or anomalous left coronary artery from the pulmonary a bradyarrhythmia.24,48 artery (ALCAPA) being the most common.43 When the left coronary artery arises from the right sinus of Valsalva, as in the pa- Dilated Cardiomyopathy tients with AOCA, the artery can course between the aorta and Dilated cardiomyopathy (DCM) is the second most common pulmonary artery with compression of the coronary artery pro- cardiomyopathy in general populations and the most common in ducing ischemia during times of increased cardiac output. In a pa- pediatric and adolescent patients, with an incidence of 0.57 per tient with ALCAPA, coronary perfusion pressure is low because 100,000 individuals.36 Unlike HCM, SCD is not a common pre- of run-off into the pulmonary artery and the myocardium experi- sentation in pediatric DCM.11,38 The highest risk of death occurs ences ischemia during times of increased demand. Coronary ar- in the first year after diagnosis, generally as a result of heart fail- tery abnormalities may also be acquired, for example, coronary ure.51 Two recent studies after pediatric patients with cardiomyop- artery ectasia seen as a complication of Kawasaki disease.9 athy showed the long-term incidence for SCD in patients with Presentation of ACOA usually occurs during adolescence or DCM at 3% to 5%.38,52 Etiology of DCM includes familial or ge- later, whereas ALCAPA is generally detected in infancy as the netic, autoimmune, toxin-induced, and infectious myocarditis.33 pulmonary artery pressures drop but, in some cases, may become Findings on physical examination depend on disease pro- evident much later in life. Complaints of early fatigue, angina, or gression. In patients with symptomatic heart failure, exaggerated exercise-induced syncope may lead to a directed evaluation. Un- precordial impulse, S3/S4 gallop, organomegaly, and signs of pe- fortunately, SCD is frequently the presenting sign.44 Patients with ripheral and pulmonary edema may be present. A mitral valve coronary ectasia after Kawasaki disease are at an increased risk for murmur can be present in cases of extreme LV dilation. Findings subsequent thrombosis or stenosis and may present with SCD.45,46 on chest radiographs and ECG demonstrate cardiomegaly, and Physical examination results can be normal in patients with echocardiogram confirms a dilated, poorly functioning left ventri- coronary anomalies.44 When symptomatic, ALCAPA can present cle. Cardiac MRI and cardiac catheterization can be used to fur- in young patients with symptoms of heart failure (feeding intoler- ther define etiology and to potentially dictate therapy but are not ance, tachypnea) related to low cardiac output. Physical examina- necessary for diagnosis. tion may reveal S3/S4 gallop, signs of pulmonary edema, and mitral valve regurgitation. Older patients are often asymptomatic Myocarditis at rest and may present with SCD during exertion.44 Characteristic Myocarditis results from infection and/or inflammation of findings on ECG of an anterolateral infarct pattern (deep and wide the heart due to a variety of causes and has been stated to be the Q waves in leads I, aVL, V5, and V6 with absent Q waves in leads most common cause of heart failure in a previously healthy pedi- II, III, and aVF and poor R wave progression) along with these ex- atric patient.53 Initial presentation may be similar to any routine vi- amination findings should raise suspicion. In general, however, ral infection with nonspecific prodromal symptoms such as anomalies may be difficult to diagnose by examination or with a dyspnea, cough, irritability, diarrhea, myalgias, or fever. Respira- routine echocardiogram and may require additional screening, tory symptoms are most common, with 69% of patients reporting such as cardiac MRI, computed tomography angiography, or ulti- a history of dyspnea. Additional history may include emesis mately cardiac catheterization.47 (48%), poor feeding (40%), fever (36%), or lethargy (36%).53 The physical examination in a patient with myocarditis is Arrhythmic Channelopathies similar to that in DCM, with tachypnea (60%), hepatomegaly Determining the contribution of arrhythmic channelopathies (50%), and tachycardia (32%).53 Diagnostic testing reveals that in SCD in pediatric and adolescent patients is difficult. Findings 63% of patients had cardiomegaly on chest radiograph, 97% with on examination or autopsy are often normal, and definitive diagno- abnormal echocardiogram, and 100% with abnormal ECG, with sis is only made if tissue is available for genetic testing or in cases of the rhythm most commonly documented to be sinus tachycardia. elucidative family history. Although there are cases where SCD Other ECG findings include supraventricular tachycardia, ventric- seems to be the presenting event, often on further review, patients ular tachycardia, atrioventricular block, low QRS voltages, T-wave may have had recurrent syncopal events or presumed seizures. abnormalities, and pseudoinfarcts.53 Cardiac enzymes may be el- Findings of physical examination are usually normal, but the evated, such as cardiac troponin T.54,55 Cardiac troponin T has a surface 12-lead ECG may offer clues. More common causes of sensitivity of 100% and a specificity of 85% for myocarditis when these arrhythmias include LQTS and CPVT.48 In LQTS, ECGs levels are greater than 0.01 ng/mL.55 Cardiac MRI can be used to

Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Pediatric Emergency Care • Volume 32, Number 9, September 2016 Sudden Cardiac Arrest in Pediatrics confirm the diagnosis in suspected myocarditis.56 The specific in certain situations such as in HCM; however, this should be etiology is difficult to define unless a myocardial biopsy is per- interpreted with cardiology consultation.62 formed with polymerase chain reaction testing for the most If the diagnosis seems to be cardiac, care should be focused common viruses. on decreasing the potential for a recurring arrhythmia and maintaining cardiac preload. Catecholamine support with agents such Restrictive Cardiomyopathy as dopamine, dobutamine, epinephrine, and norepinephrine for Restrictive cardiomyopathy (RCM) accounts for less than postresuscitation hypotension should be avoided or used with extreme caution because they may worsen symptoms of obstruction 5% of diagnosed cardiomyopathies and is a relatively rare cause 41,62,63 of SCD.57 Despite this low occurrence, transplant-free survival in a patient with HCM or potentiate arrhythmias. in RCM is typically low, in part because of arrhythmic events.58 Benzodiazepines should be used with caution because they can result in hypotension, decrease afterload, and subsequently re- Given the low incidence of disease, limited follow-up data are 42 available to track SCA and SCD in patients with RCM. Between duce coronary blood flow. Medications recommended for intuba- a small, single institution series and a larger registry, SCD oc- tion in patients with cardiac disease include etomidate or fentanyl curred in 10% to 12% of patients with a long-term follow-up.38,59 and midazolam for sedation with vecuronium or rocuronium for pa- ralysis because they may produce less sympathetic response to intu- Physical examination can include gallop, loud second heart 42,64,65 sound (closure of the pulmonary valve or P2), or murmur.58 Due bation. Vecuronium has been suggested for certain structural to diastolic dysfunction, the most common presentation within a heart disease because of its histamine release, vagolytic, and mus- cohort of RCM patients who ultimately experienced SCD was carinic activity, whereas some sources recommend rocuronium 58 for arrhythymogenic heart disease because of a lower rate of syncope. Findings of ECG are abnormal in most cases, with ev- 42,66 idence for atrial enlargement being pathognomonic. Chest radio- bradyarrhythmias. A summary of these recommendations graph findings may also be abnormal, showing cardiomegaly, can be found in Figure 1. atrial enlargement, or pulmonary venous congestion.57,58 Echo- Prevention of SCA is generally outside the scope of ED care, cardiograms can reveal atrial dilation in the setting of normal sized especially regarding the extensive literature and recommendations 59 on primary prevention screening programs for athletes in an out- ventricles, with evidence for elevated filling pressures. Cardiac 67 catheterization, with measurement of elevated end-diastolic pres- patient setting. However, emergency physicians who treat pedi- sures, is diagnostic. atric patients may be involved in secondary preventative efforts such as evaluation of symptomatic cardiac patients before arrest Other Causes and community involvement in prehospital care. Evaluation of cardiac complaints, such as exertional fatigue, chest pain, palpita- Less-common causes for SCD include congenital heart dis- tions, and syncope, as well as symptoms such as vomiting, dys- ease, C. cordis, and medication-related. Congenital heart disease pnea, and abnormal movement concerning for seizure should be poses the challenge of not only structural defects but also conduc- 48 thoroughly and thoughtfully managed to prevent cases of SCA. tion abnormalities. Presentation and diagnosis vary with disease It is estimated that 24% of SCA patients have had 1 or more epi- process. Commotio cordis is a rare cause of SCD and presents sodes of syncope or unexplained seizure before presentation.68 when a blow to the chest occurs during repolarization (the Twave 48 Although cardiac causes of syncope are rare, evaluation by ECG on ECG) and causes VF. Finally, multiple medications, espe- can differentiate these cases from benign causes, with 76% posi- cially stimulants (such as cocaine) and QT prolonging medica- tive for abnormal findings in cardiac syncope versus 0% positive tions (certain antibiotics, antifungals, and psychotropics, etc at in noncardiac syncope.69 In the evaluation of patients with con- high doses or multiple agents usually in patients with risk factors cerning symptoms or family history, standardized screening tools such as genetic predisposition, cardiac disease, and hypokalemia/ such as the “12-Element American Heart Association Recom- hypomagnesemia), can precipitate arrhythmias and cause SCA 7,60 mendations for Pre-participation Cardiovascular Screening for or SCD. Competitive Athletes” or the American Academy of Pediatrics “Pediatric Sudden Cardiac Death Risk Assessment Form” are rec- EMERGENCY INTERVENTIONS ommended.7,70 Prehospital care is vital to a positive outcome, be- When treating a patient who has recently experienced or is cause early cardiopulmonary resuscitation and defibrillation with currently in cardiac arrest, emergency care should follow Pediatric an automated external defibrillator (AED) can result in survival Advanced Life Support guidelines.61 While the patient is being sta- rates of up to 74%.71 Efforts to increase AED presence on high bilized, a brief history, focused physical examination, and initial di- school campuses and throughout communities are effective and agnostics should be performed. As stated in Pediatric Advanced continue to improve overall survival.72 Life Support guidelines, amiodarone should be considered if a pa- Even with ideal prehospital and emergency interventions, tient has arrhythmias unresponsive to defibrillation.27 Intractable survival rates for SCA are poor, with an average of 11% survival arrhythmias are most commonly seen in patients with HCM. Al- of those with exercise-related events in school-aged children older though taking an extensive history is difficult in the emergency set- than 6 years.73 However, 50% of previously healthy children pre- ting, questions about history of present illness, previous history of senting to a pediatric ICU after an out-of-hospital SCA survived to chest pain, dyspnea and/or syncope during exertion, as well as fam- discharge, with half of the identified etiologies being cardiac.74 Of ily history of cardiac illnesses are essential in determining the etiol- those children who survived, 50% had minimal neurocognitive ogy of the arrest. disabilities with full functional capacity at 6 months; however, Physical examination should focus on circulation, airway, many continue to have memory deficits and psychological prob- and breathing until the patient is stable; then, a more comprehensive lems.75 Despite this progress, there is a need to improve outcomes examination including a detailed cardiac examination may reveal of patients presenting with SCA. pertinent findings. Cardiorespiratory monitors should be placed along with defibrillator pads to monitor for immediate recognition of an abnormal rhythm. Diagnostics should always include a CASE RESOLUTION 12-lead ECG and a chest radiograph. If there are additional The child was transferred from the ED to the pediatric ICU, concerns, point-of-care ultrasound has been shown to be useful where he was weaned off inotropes and extubated. A transvenous

FIGURE 1. Emergency provider evaluation and initial management of possible pediatric SCA. single-coil implantable cardioverter defibrillator was placed on be employed to exclude treatments that could exacerbate the un- day 5 of hospitalization for secondary prevention due to the play- derlying condition. Our understanding of the etiologies of SCD ground event being most likely a ventricular arrhythmia. He was and SCA is improving, and the addition of a collaborative national discharged 6 days after presentation. registry will continue to advance the field.23 At the postresuscitation review of the ED care, there were interventions that were helpful for his condition and others that REFERENCES could have been detrimental. For example, fluids were important to maintain the patient's preload and therefore blood pressure. 1. Scheller RLJL, Caruso MC, Lorts A. Sudden collapse of a preschool-aged Medications for possible seizure precautions such as midazolam child on the playground. Pediatr Emerg Care.October13,2015. and fosphenytoin could have deleterious effects on maintaining doi:10.1097/PEC.0000000000000547. his blood pressure. Use of an epinephrine drip for pressor support 2. Zipes DP, Wellens HJ. Sudden cardiac death. Circulation.1998;98: could have worsened afterload or potentiated an arrhythmia. As 2334–2351. the patient was stabilized and more detailed history was provided 3. Wren C. Cardiac causes for syncope or sudden death in childhood. Arch including that the collapse occurred during exertion, a cardiac Dis Child. 1999;81:289–291. cause for his SCA became more apparent. In addition, physical 4. Liberthson RR. Sudden death from cardiac causes in children and young examination revealed a murmur, which may have been difficult adults. NEnglJMed. 1996;334:1039–1044. to detect in the resuscitation room. This case illustrates an episode of SCA in which successful resuscitative efforts prevented a case 5. Kaltman JR, Thompson PD, Lantos J, et al. Screening for sudden cardiac of SCD.1 death in the young: report from a national heart, lung, and blood institute working group. Circulation. 2011;123:1911–1918. CONCLUSIONS 6. Driscoll DJ, Edwards WD. Sudden unexpected death in children and – The presentation of sudden collapse can have myriad etiolo- adolescents. J Am Coll Cardiol. 1985;5(suppl 6):118B 121B. gies, and the underlying cause difficult to discern on initial evalu- 7. Section on Cardiology and Cardiac Surgery. Pediatric sudden cardiac ation in the ED. Maintaining a wide differential diagnosis and arrest. Pediatrics. 2012;129:e1094–e1102. using diagnostics to consider cardiac etiologies are essential. If 8. Corrado D, Basso C, Schiavon M, et al. Screening for hypertrophic cardiac etiologies are suspected, deliberate management should cardiomyopathy in young athletes. NEnglJMed. 1998;339:364–369.

9. Berger S, Campbell RM. Sudden cardiac death in children and adolescents: 32. Pilmer CM, Kirsh JA, Hildebrandt D, et al. Sudden cardiac death in introduction and overview. Pacing Clin Electrophysiol. 2009;32(suppl 2): children and adolescents between 1 and 19 years of age. Heart Rhythm. S2–S5. 2014;11:239–245. 10. Spurgeon D. Sudden cardiac deaths rise 10% in young Americans. BMJ. 33. Durante A, Laforgia PL, Aurelio A, et al. Sudden cardiac death in the 2001;322:573. young: the bogeyman. Cardiol Young. 2015;25:408–423. 11. Wren C. Sudden death in children and adolescents. Heart.2002;88: 34. Berger S, Kugler JD, Thomas JA, et al. Sudden cardiac death in children 426–431. and adolescents: introduction and overview. Pediatr Clin North Am.2004; – 12. Neuspiel DR, Kuller LH. Sudden and unexpected natural death in 51:1201 1209. childhood and adolescence. JAMA. 1985;254:1321–1325. 35. Maron BJ, Gardin JM, Flack JM, et al. Prevalence of hypertrophic 13. SoRelle R. Jump in sudden cardiac deaths reported in younger people cardiomyopathy in a general population of young adults. during past decade. Circulation. 2001;103:E9019–E9021. Echocardiographic analysis of 4111 subjects in the CARDIA Study. Coronary Artery Risk Development in (Young) Adults. Circulation.1995; 14. Maron BJ, Epstein SE, Roberts WC. Causes of sudden death in competitive 92:785–789. athletes. J Am Coll Cardiol. 1986;7:204–214. 36. Lipshultz SE, Sleeper LA, Towbin JA, et al. The incidence of pediatric 15. Waller BF, Hawley DA, Clark MA, et al. Incidence of sudden athletic cardiomyopathy in two regions of the United States. NEnglJMed. 2003; deaths between 1985 and 1990 in Marion County, Indiana. Clin Cardiol. 348:1647–1655. 1992;15:851–858. 37. Maron BJ, Rowin EJ, Casey SA, et al. Hypertrophic cardiomyopathy in 16. Steinberger J, Lucas RV Jr, Edwards JE, et al. Causes of sudden unexpected children, adolescents, and young adults associated with low cardiovascular cardiac death in the first two decades of life. Am J Cardiol.1996;77: mortality with contemporary management strategies. Circulation.2016; – 992 995. 133:62–73. 17. Maron BJ, Shirani J, Poliac LC, et al. Sudden death in young competitive 38. Bharucha T, Lee KJ, Daubeney PE, et al. Sudden death in childhood athletes. Clinical, demographic, and pathological profiles. JAMA. 1996; cardiomyopathy: results from a long-term national population-based study. – 276:199 204. J Am Coll Cardiol. 2015;65:2302–2310. 18. Maron BJ, Gohman TE, Aeppli D. Prevalence of sudden cardiac death 39. Maron BJ. Hypertrophic cardiomyopathy: a systematic review. JAMA. during competitive sports activities in Minnesota high school athletes. JAm 2002;287:1308–1320. Coll Cardiol. 1998;32:1881–1884. 40. Gersh BJ, Maron BJ, Bonow RO, et al. 2011 ACCF/AHA Guideline for the 19. Basso C, Corrado D, Thiene G. Cardiovascular causes of sudden death in Diagnosis and Treatment of Hypertrophic Cardiomyopathy: a report of the – young individuals including athletes. Cardiol Rev. 1999;7:127 135. American College of Cardiology Foundation/American Heart Association 20. Thiene G, Basso C, Corrado D. Is prevention of sudden death in young Task Force on Practice Guidelines. Developed in collaboration with the athletes feasible? Cardiologia. 1999;44:497–505. American Association for Thoracic Surgery, American Society of 21. Wisten A, Forsberg H, Krantz P, et al. Sudden cardiac death in 15–35-year Echocardiography, American Society of Nuclear Cardiology, Heart Failure olds in Sweden during 1992-99. JInternMed. 2002;252:529–536. Society of America, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. JAm 22. Harmon KG, Drezner JA, Wilson MG, et al. Incidence of sudden cardiac Coll Cardiol.2011;58:e212–260. death in athletes: a state-of-the-art review. Br J Sports Med.2014;48: 1185–1192. 41. Fleisher GR, Ludwig S. Textbook of Pediatric Emergency Medicine.6thed. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins 23. Mitka M. US registry for sudden death in the young launched by the Health; 2010. NIH and CDC. JAMA. 2013;310:2495. 42. Poliac LC, Barron ME, Maron BJ. Hypertrophic cardiomyopathy. 24. Campbell RM, Berger S, Drezner J. Sudden cardiac arrest in children Anesthesiology. 2006;104:183–192. and young athletes: the importance of a detailed personal and family history in the pre-participation evaluation. Br J Sports Med.2009;43: 43. Lipsett J, Cohle SD, Berry PJ, et al. Anomalous coronary arteries: a – 336–341. multicenter pediatric autopsy study. Pediatr Pathol. 1994;14:287 300. 25. Meyer L, Stubbs B, Fahrenbruch C, et al. Incidence, causes, and survival 44. Frommelt PC, Frommelt MA. Congenital coronary artery anomalies. – trends from cardiovascular-related sudden cardiac arrest in children and Pediatr Clin North Am. 2004;51:1273 1288. young adults 0 to 35 years of age: a 30-year review. Circulation. 2012;126: 45. Tsuda E, Arakaki Y, Shimizu T, et al. Changes in causes of sudden deaths 1363–1372. by decade in patients with coronary arterial lesions due to Kawasaki – 26. Maron BJ, Doerer JJ, Haas TS, et al. Sudden deaths in young competitive disease. Cardiol Young. 2005;15:481 488. athletes: analysis of 1866 deaths in the United States, 1980-2006. 46. Wei YJ, Zhao XL, Liu BM, et al. Cardiac complications in 38 cases of Circulation. 2009;119:1085–1092. Kawasaki disease with coronary artery aneurysm diagnosed by – 27. Richman PB, Nashed AH. The etiology of cardiac arrest in children and echocardiography. Echocardiography. 2016;33:764 770. young adults: special considerations for ED management. Am J Emerg 47. Walsh R, Nielsen JC, Ko HH, et al. Imaging of congenital coronary artery Med. 1999;17:264–270. anomalies. Pediatr Radiol. 2011;41:1526–1535. 28. Puranik R, Chow CK, Duflou JA, et al. Sudden death in the young. Heart 48. Gajewski KK, Saul JP. Sudden cardiac death in children and adolescents Rhythm. 2005;2:1277–1282. (excluding sudden infant death syndrome). Ann Pediatr Cardiol.2010;3: – 29. Sirbaugh PE, Pepe PE, Shook JE, et al. A prospective, population-based 107 112. study of the demographics, epidemiology, management, and outcome of 49. Vincent GM, Timothy KW, Leppert M, et al. The spectrum of symptoms out-of-hospital pediatric cardiopulmonary arrest. Ann Emerg Med.1999; and QT intervals in carriers of the gene for the long-QT syndrome. NEnglJ 33:174–184. Med. 1992;327:846–852. 30. Young KD, Seidel JS. Pediatric cardiopulmonary resuscitation: a collective 50. Tester DJ, Will ML, Ackerman MJ. Mutation detection in congenital long review. Ann Emerg Med. 1999;33:195–205. QT syndrome: cardiac channel gene screen using PCR, dHPLC, and direct – 31. Winkel BG, Risgaard B, Sadjadieh G, et al. Sudden cardiac death in DNA sequencing. Methods Mol Med. 2006;128:181 207. children (1-18 years): symptoms and causes of death in a nationwide 51. Alexander PM, Daubeney PE, Nugent AW, et al. Long-term outcomes of setting. Eur Heart J. 2014;35:868–875. dilated cardiomyopathy diagnosed during childhood: results from a

national population-based study of childhood cardiomyopathy. Circulation. adolescents with hypertrophic cardiomyopathy. J Am Coll Cardiol.2013; 2013;128:2039–2046. 61:1527–1535. 52. Pahl E, Sleeper LA, Canter CE, et al. Incidence of and risk factors for 64. Staikou C, Chondrogiannis K, Mani A. Perioperative management of sudden cardiac death in children with dilated cardiomyopathy: a report hereditary arrhythmogenic syndromes. Br J Anaesth. 2012;108:730–744. from the Pediatric Cardiomyopathy Registry. J Am Coll Cardiol.2012;59: 65. Hamid A. Anesthesia for cardiac catheterization procedures. Heart Lung – 607 615. Ve s s el .2014;6:225–231. 53. Durani Y, Egan M, Baffa J, et al. Pediatric myocarditis: presenting clinical 66. Harvey A, Anderson L, Broome IJ. A comparison of the effect of characteristics. Am J Emerg Med. 2009;27:942–947. rocuronium and vecuronium on heart rate during gynaecological – 54. Kantor PF, Lougheed J, Dancea A, et al. Presentation, diagnosis, and laparoscopy. Anaesthesia. 1999;54:1212 1216. medical management of heart failure in children: Canadian Cardiovascular 67. Vetter VL. Best practices for ECG screening in children. J Electrocardiol. Society guidelines. Can J Cardiol. 2013;29:1535–1552. 2015;48:316–323. 55. Eisenberg MA, Green-Hopkins I, Alexander ME, et al. Cardiac troponin 68. Drezner JA, Fudge J, Harmon KG, et al. Warning symptoms and family Tas a screening test for myocarditis in children. Pediatr Emerg Care.2012; history in children and young adults with sudden cardiac arrest. JAmBoard 28:1173–1178. Fam Med. 2012;25:408–415. 56. Friedrich MG, Sechtem U, Schulz-Menger J, et al. Cardiovascular 69. Tretter JT, Kavey RE. Distinguishing cardiac syncope from vasovagal magnetic resonance in myocarditis: A JACC White Paper. JAmColl syncope in a referral population. J Pediatr. 2013;163:1618–1623 e1611. Cardiol. 2009;53:1475–1487. 70. Maron BJ, Thompson PD, Ackerman MJ, et al. Recommendations and 57. Denfield SW. Sudden death in children with restrictive cardiomyopathy. considerations related to preparticipation screening for cardiovascular Card Electrophysiol Rev. 2002;6:163–167. abnormalities in competitive athletes: 2007 update: a scientific statement from the American Heart Association Council on Nutrition, Physical 58. Denfield SW,Webber SA. Restrictive cardiomyopathy in childhood. Heart Activity, and Metabolism: endorsed by the American College of Fail Clin. 2010;6:445–452, viii. Cardiology Foundation. Circulation. 2007;115:1643–1455. 59. Rivenes SM, Kearney DL, Smith EO, et al. Sudden death and 71. Vetter VL, Haley DM. Secondary prevention of sudden cardiac death: cardiovascular collapse in children with restrictive cardiomyopathy. does it work in children? Curr Opin Cardiol.2014;29:68–75. Circulation. 2000;102:876–882. 72. Toresdahl B, Courson R, Börjesson M, et al. Emergency cardiac care 60. Marzuillo P, Benettoni A, Germani C, et al. Acquired long QT syndrome: in the athletic setting: from schools to the Olympics. Br J Sports Med. – a focus for the general pediatrician. Pediatr Emerg Care. 2014;30:257 261. 2012;46(suppl 1):i85–i89. 61. Kleinman ME, Chameides L, Schexnayder SM, et al. Part 14: pediatric 73. Drezner JA, Chun JS, Harmon KG, et al. Survival trends in the advanced life support: 2010 American Heart Association Guidelines for United States following exercise-related sudden cardiac arrest in the Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. youth: 2000-2006. Heart Rhythm.2008;5:794–799. Circulation. 2010;122(18 suppl 3):S876–S908. 74. Alapati S, Strobel N, Hashmi S, et al. Sudden unexplained cardiac arrest 62. Zhang S, Zhu D, Wan Z, et al. Utility of point-of-care echocardiogram in in apparently healthy children: a single-center experience. Pediatr Cardiol. the rapid diagnosis of hypertrophic cardiomyopathy. Am J Emerg Med. 2013;34:639–645. 2013;31:1280–1282. 75. Maryniak A, Bielawska A, Walczak F, et al. Long-term cognitive 63. Maron BJ, Spirito P, Ackerman MJ, et al. Prevention of sudden cardiac outcome in teenage survivors of arrhythmic cardiac arrest. Resuscitation. death with implantable cardioverter-defibrillators in children and 2008;77:46–50.

CME EXAM INSTRUCTIONS FOR OBTAINING AMA PRA CATEGORY 1 CREDITSTM Pediatric Emergency Care includes CME-certified content that is designed to meet the educational needs of its readers. An annual total of 12 AMA PRA Category 1 CreditsTM is available through the twelve 2016 issues of Pediatric Emergency Care.Thisactivityis available for credit through August 31, 2017. The CME activity is now available online. Please visit http://CME.LWW.com for more information about this educational offering and to complete the CME activity.

CME EXAMINATION September 2016 Please mark your answers on the ANSWER SHEET. Sudden Cardiac Arrest in Pediatrics, Scheller et al.

1. What is the most common underlying cardiac structural abnormal- ity that results in sudden cardiac death? 4. Which medication(s) should be used with caution in a patient A. Myocarditis suspected to have arrhythmic etiology for the sudden arrest? B. Hypertrophic cardiomyopathy A. Dopamine C. Coronary artery anomaly B. Vecuronium D. Idiopathic C. Etomidate D. A and B 2. The risk for sudden cardiac death in athletes compared with age E. All of the above matched nonathletes is: A. Less than 0.5 times relative risk 5. Of prevention methods for sudden cardiac death, which is in the B. Statistically similar scope of an emergency medicine provider? C. More than 2 times relative risk A. School support of AEDs D. Inadequately studied B. Evaluating all athletes with ECGs C. Screening of cardiac complaints 3. ECGs findings in patients with hypertrophic cardiomyopathy D. A and C only are abnormal in what percentage of patients? E. All of the above A. 1%–10% B. 25%–50% C. 75%–90% D. 100%

ANSWER SHEET FOR THE PEDIATRIC EMERGENCY CARE CME PROGRAM EXAM September 2016 Please answer the questions on page 637 by filling in the appropriate circles on the answer sheet below. Please mark the one best answer and fill in the circle until the letter is no longer visible. To process your exam, you must also provide the following information: Name (please print): ______Street Address ______City/State/Zip ______Daytime Phone ______Specialty ______1. A B C D E 2. A B C D E 3. A B C D E 4. A B C D E 5. A B C D E Your completion of this activity includes evaluating them. Please respond to the following questions below. Please rate this activity (1 - minimally, 5 - completely) 12345 Was effective in meeting the educational objectives Was appropriately evidence-based Was relevant to my practice Please rate your ability to achieve the following objectives, both before this activity and after it: 1 (minimally) to 5 (completely) Pre Post 12345 12345 1. Outline the possible cardiac causes of sudden arrest in children and adolescents. 2. Describe emergency care of a pediatric sudden cardiac arrest patient. 3. Identify disease-specific presentation of cardiac causes of sudden arrest in children and adolescents. How many of your patients are likely to be impacted by what you learned from these activities? ○ <20% ○ 20%–40% ○ 40%–60% ○ 60%–80% ○ >80% Do you expect that these activities will help you improve your skill or judgment 12345 within the next 6 months? (1 - definitely will not change, 5 - definitely will change) How will you apply what you learned from these activities (mark all that apply): In diagnosing patients ○ In making treatment decisions ○ In monitoring patients ○ As a foundation to learn more ○ In educating students and colleagues ○ In educating patients and their caregivers ○ As part of a quality or peformance improvement project ○ To confirm current practice ○ For maintenance of board certification ○ For maintenance of licensure ○ To consider enrolling patients in clinical trials ○ Other ______Please list at least one strategy you learned from this activity that you will apply in practice: How committed are you to applying these activities to your practice in the ways 12345 you indicated above? (1 - minimally, 5 - completely) Did you perceive any bias for or against any commercial products or devices? Yes No

If yes, please explain: How long did it take you to complete these activities? ______hours ______minutes What are your biggest clinical challenges related to pediatric emergency care? [ ] Yes! I am interested in receiving future CME programs from Lippincott CME Institute! (Please place a check mark in the box )

Mail by August 31, 2017 to Lippincott CME Institute, Inc. Wolters Kluwer Health Two Commerce Square 2001 Market Street, 3rd Floor Philadelphia, PA 19103